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The purpose of this paper is to study the influence of different factors on mud performance, find the best conditions and synthesize a new type of anti-collapse drilling polymer mud with higher stability. The anti-collapse mechanism of drilling polymer mud was also suggested.

Exploring the influence of different molecular weight thickeners, filtrate reducers, soda ash addition and film-forming components on the mud performance, so as to obtain the best ratio of anti-collapse drilling polymer mud.

The results show that the use of vegetable glue, sulfonate copolymer and vegetable fiber powder can synthesize a high-viscosity, high-stability, collapse-resistant mud. When the mass ratio of vegetable fiber powder: vegetable glue: sulfonate copolymer is 40:1:2, the mud viscosity is 21.2 s, the fluid loss in 30 min is only 12.5 mL, and the mud film thickness is 1.5 mm, which is one ideal anti-collapse polymer mud.

Compared with ordinary polymer mud and bentonite mud, this anti-collapse polymer mud not only uses vegetable glue instead of traditional tackifiers but also effectively uses vegetable fiber powder produced from waste wood, which is environmentally friendly and highly stable specialty. It can effectively improve the safety and quality of construction during drilling in water-sensitive geology.

This study seeks to explore the relationship between performance relative to aspiration and SMEs' internationalization speed, and moderating effects of top management's policy knowledge and institutional distance between the above relation.

This study tests the authors’ hypotheses using data on Chinese manufacturing SMEs over a 5-year period from 2013 to 2017. The authors leverage archival panel data on publicly listed companies on the SME Board, GEM and New OTC Market in the Shanghai and Shenzhen Stock Exchanges. The authors then collected data from the WIND and ZEPHYR databases.

The results confirm a U-shaped relation between performance relative to aspiration and SMEs' internationalization speed, and show that this relation is steepening by top management's policy knowledge in home country but flattening by institutional distance as environmental dynamics.

The study findings contribute to the international business field by exploring how a firm's risk situation in internationalization can change, thereby influencing SMEs' international expansion.

The purpose of this paper is to contribute to a unified theory of entrepreneurial orientation. To this end, the study considers the nexus of entrepreneurial orientation and venture performance contingent on entrepreneurial political skill, as well as in relation to organizational justice as it influences stakeholder commitment.

A diverse sample of 237 entrepreneurs from private entrepreneurial enterprises throughout an eastern province (Zhejiang) of China participated in a questionnaire study during three years. The study applies structural equation modeling and hierarchical moderated regression analyses to test the hypotheses.

In the context of a developing economy (China), the study verifies the influence of entrepreneurial political skill on entrepreneurial performance. Amongst those involved in the venture, a sense of organizational justice combined with entrepreneurial orientation work to moderate the entrepreneur’s political skill in achieving outcomes.

Limitations of the study are the questionnaire survey identifies entrepreneurial “perceptions” of success or failure with actual success or failure; and responses are weighted to founders and top managers as representing entrepreneurial actors more generally.

The study concludes that access to scarce resources and maintenance of goal congruence are more likely to be achieved when entrepreneurial innovativeness and pro-activeness are combined with entrepreneurial political skill in a setting of organizational justice.

The study finds that entrepreneurs are able to improve performance by instilling a group culture of trust and social justice.

The study is located contextually in the guanxi-centered social exchange atmosphere of China as the economy transforms from a planned to a market model, with institutional arrangements of a mixed economy of state-owned and privately owned enterprises. In this context, the study explores the constructs of entrepreneurial orientation in relation to entrepreneurial political skill in a context of organizational justice as they combine to influence a venture’s success.

With continuous concerning on the toxic of element Pb, Pb-free solder was gradually used to replace traditional Sn-Pb solder. However, during the transition period from Sn-Pb to Pb-free solder, mixing of Sn-Pb and Pb-free is inevitable occurred in certain products, and in China where Sn-Pb solder was still used extensively in certain areas especially. Correspondingly, understanding reliability of Sn-Pb solder joints was very important, and further studies were needed.

Thermal shock test between −55°C and 125 °C was conducted on Sn-37Pb solder bumps in the BGA package to investigate the microstructure evolution and the growth mechanism of interfacial intermetallic compound (IMC) layer. The effects of thermal shock on the mechanical property and fracture behavior of Sn-37Pb solder bumps were discussed.

Pb-rich phase was coarsened and voids were increased at first; Pb-rich phase was refined and voids were decreased secondly with the increase of thermal shock cycles; the shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67MPa at 2,000 cycles; interfacial IMCs of solder bumps was from typical scallop-type into smooth, the composition of IMCs was from Cu₆Sn₅ into Cu₆Sn₅ and Cu₃S_n after thermal shock with 1,500 and 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure respectively.

Compared with the board level test method, the impact shear test for the single solder bump is more convenient and economical and is actively pursued by the industries. The shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67 MPa at 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure.

The purpose of this paper is to provide an optimization method of robot cladding path, which is helpful to solve the problem of path under-optimization in laser cladding forming (LCF) based on robot.

First, the error influence parameters need setting before the cladding path generation, and the model of seeking appropriate error influence parameters is established based on the particle swarm optimization (PSO). Second, to solve the problem of collapse during the LCF process, the reason for collapse is analyzed and a robot cladding path error optimization method based on the layer path interpolation is proposed. Finally, the simulation and experiments are carried out.

Under the premise of giving the expected error of stereo lithography (STL) model, the optimal range of the chord height and the angle control can be quickly found by using PSO algorithm. Aiming at the collapse problem in the laser cladding process, a robot cladding path optimization method based on the layer path interpolation is proposed. A four-layer path interpolation simulation and the contrast experiments before and after the path optimization are completed; the results show that the robot cladding path optimization method can solve the problem of the collapse in laser cladding.

Robot cladding path optimization is one of the key technologies of LCF, and the quality of the robot cladding path is affected by STL model error and the path optimization method. This paper proposed a robot cladding path optimization method for LCF. This method can be used in other additive manufacturing techniques.

The quality of cladding path is important for LCF; this paper first proposed the optimization method of the robot cladding path for LCF to solve the collapse problem.

The aim of this paper is to investigate the growth behaviours of intermetallic compound (IMC) layers in solid‐liquid interfacial reactions of Sn1.5Cu/Cu in various intensities of high‐magnetic field.

Sn1.5Cu solder was prepared and melted in a vacuum furnace at 873 K and cast into solder bars. Samples were mounted using resin and etched after being carefully polished. Then the IMC layers were observed by using scanning electron microscopy.

The results show that the growth of IMC layers has been accelerated by high‐magnetic field through the comparison of growth kinetics of IMC layers among 0‐2.5 T magnetic filed. IMC grains in high‐magnetic field are much bigger than that in 0 T. By the analyzing of X‐ray diffractometer patterns of IMC layers, it can be found that the orientations of IMC have been changed by magnetic field.

This paper investigates the growth behaviour of IMC layers during the solid‐liquid interfacial reactions of Sn1.5Cu/Cu in a high magnetic field.

Network embeddedness has been widely considered in enterprise innovation as an effective means of overcoming resource dilemmas. However, while focussing on acquiring external innovation resources, the existing research often ignores the vital role of internal routine updates. Therefore, this study explores the mechanism by which network embeddedness affects innovation performance of enterprises from the perspective of organisational routine updating.

This paper proposes a theoretical model based on social network theory and organisational routines–immune response theory. A total of 328 pieces of research data on high-tech enterprises in China were collected, and the hypotheses were verified using hierarchical regression analysis.

The results show that the two forms of network embeddedness – structural embeddedness and relational embeddedness, have a positive effect on enterprise innovation performance and a significant positive effect on organisational routine revision and organisational routine creation. Both organisational routine revision and organisational routine creation positively affect enterprise innovation performance and partially mediate the relationship between network embeddedness and enterprise innovation performance.

This conclusion provides a new perspective on the impact of network embeddedness on enterprise innovation performance and expands the related research on organisational routine updating. This study provides a theoretical reference for high-tech enterprises to improve their competitiveness and innovation performance through network embeddedness and organisational routine updating.

The purpose of this paper is to compare Google Books with WorldCat and to assess some other functionalities of Google Books.

Over 500 random samples generated from WorldCat were searched on Google Books. The search results were used to compare the coverage between Google Books and WorldCat, to estimate the successful link rate to a local library catalogue, the percentage available as full view, snippet, and preview on Google Books, and other services of Google Books.

Google Books can retrieve almost all the books catalogued in WorldCat. Its “Find in a library” link to a local library catalogue works 75 percent of the time. Fewer than 10 percent of Google Books items have free full views, and about 15 percent have snippets and previews, respectively. Previews are much more useful than snippets. Google Books probably indexes books that it does not possess in digital form, in addition to indexing all the books that it has acquired in digital form.

No previous empirical studies of this kind have been found. This study assesses Google Books' coverage and services with quantitative measures.

The purpose of this paper is to provide the historical background of genealogical records and analyze the value of Chinese genealogical research through the study of names and genealogical resources.

The paper examines the historical evolution and value of Chinese genealogical records, with the focus on researching the Islamic Chinese names used by the people living in Guilin. The highlight of this paper includes the analysis and evolution of the Islamic Chinese names commonly adopted by the local people in Guilin. It concludes with the recommendations on emphasizing and making the best use of genealogical records to enhance the research value of Chinese overseas studies.

The paper covers the history of Islam and describes how the religion was introduced into China, as well as Muslims' ethnicity and identity. It also places focus on the importance of building a research collection in Asian history and Chinese genealogy.

This research study has a strong subject focus on Chinese genealogy, Asian history, and Islamic Chinese surnames. It is a narrow field that few researchers have delved into.

The results of this study will assist students, researchers, and the general public in tracing the origin of their surnames and developing their interest in the social and historical value of Chinese local history and genealogies.

The study of Chinese surnames is, by itself, a particular field for researching the social and political implications of contemporary Chinese society during the time the family members lived.

Very little research has been done in the area of Chinese local history and genealogy. The paper would be of value to researchers such as historians, sociologists, ethnologists and archaeologists, as well as students and anyone interested in researching a surname origin, its history and evolution.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.